González-del-Hoyo M, et al. - In this retrospective cohort study of 222 Emergency Department admissions with a primary diagnosis of tachyarrhythmia, researchers intended to determine the correlation of cardiac troponin I (cTnI) levels and long-term prognosis. Analysis of patients' clinical features and 5-year all-cause mortality were carried out. High levels of cTnI were detected in 73 patients (32.9%) who were older and had significantly more cardiovascular risk factors. Five-year follow-up was performed, which revealed higher long-term mortality rates among these patients with high cTnI levels vs patients with low cTnI levels. Mortality in late follow-up could be predicted by cTnI. This shows the usefulness of cTnI in the risk stratification of these subjects.